Currently, an array substrate of a thin Film Transistor Liquid Crystal Display (TFT-LCD) is manufactured by several patterning processes, wherein each patterning process may includes photoresist applying, exposure, development, etching and peeling off etc.
The array substrate is generally manufactured by four, five or six patterning processes. For example, the method for manufacturing the array substrate by five patterning processes includes:
First, a gate metal material is deposited on a base substrate 1, and a pattern of gates 2 is formed by a first patterning process, as shown in FIG. 1;
Second, an insulation material (e.g. SiNx) is deposited so as to separate the gates 2 from a semiconductor layer to be formed subsequently, a semiconductor material a-Si is then deposited on the insulation material, and a pattern of a gate insulation layer 3 and a pattern of a semiconductor layer 4 are formed by a second patterning process, as shown in FIG. 2;
Third, a source and drain metal material is deposited, and a pattern including sources 5 and drains 6 is formed by a third patterning process, as shown in FIG. 3;
Then, an insulation material is deposited to form an insulation layer 7 (e.g. a passivation layer, PVX), and via holes 8 are formed in the insulation layer 7 by a fourth patterning layer, as shown in FIG. 4;
Finally, a transparent electrode material (i.e. an ITO thin film) is deposited, and a pattern of pixel electrodes 9 is formed by a fifth patterning process to form the array substrate, as shown in FIG. 5.
When the pixel electrodes 9 are formed by etching the ITO thin film, etching residues 10 are likely to be generated (as shown in FIG. 5), which will easily cause interconnection between two adjacent pixel electrodes.